aboutsummaryrefslogblamecommitdiffstats
path: root/main/libxxf86vm/0002-Improve-error-handling-in-XF86VidModeGetMonitor.patch
blob: 099ca99716d7e52bd264f7688e211ed4de301b42 (plain) (tree)





































































































































                                                                                                  
From a89b1ad3377bfef9bab52f15f98b00f6540d531a Mon Sep 17 00:00:00 2001
From: Alan Coopersmith <alan.coopersmith@oracle.com>
Date: Sat, 13 Apr 2013 17:40:24 -0700
Subject: [PATCH 2/8] Improve error handling in XF86VidModeGetMonitor()

Ensure that when we return an error we unlock the display first, and
NULL out any pointers we freed in error cleanup.

Instead of adding these fixes to every error check, instead combine
the error handling cleanup into a single copy.

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>
---
 src/XF86VMode.c | 82 +++++++++++++++++++++++++++------------------------------
 1 file changed, 39 insertions(+), 43 deletions(-)

diff --git a/src/XF86VMode.c b/src/XF86VMode.c
index c0e50e6..165f8ba 100644
--- a/src/XF86VMode.c
+++ b/src/XF86VMode.c
@@ -856,6 +856,7 @@ XF86VidModeGetMonitor(Display* dpy, int screen, XF86VidModeMonitor* monitor)
     xXF86VidModeGetMonitorReq *req;
     CARD32 syncrange;
     int i;
+    Bool result = True;
 
     XF86VidModeCheckExtension (dpy, info, False);
 
@@ -875,63 +876,58 @@ XF86VidModeGetMonitor(Display* dpy, int screen, XF86VidModeMonitor* monitor)
     monitor->bandwidth = (float)rep.bandwidth / 1e6;
 #endif
     if (rep.vendorLength) {
-	if (!(monitor->vendor = (char *)Xcalloc(rep.vendorLength + 1, 1))) {
-	    _XEatData(dpy, (rep.nhsync + rep.nvsync) * 4 +
-		      ((rep.vendorLength+3) & ~3) + ((rep.modelLength+3) & ~3));
-	    return False;
-	}
+	monitor->vendor = Xcalloc(rep.vendorLength + 1, 1);
+	if (monitor->vendor == NULL)
+	    result = False;
     } else {
 	monitor->vendor = NULL;
     }
-    if (rep.modelLength) {
-	if (!(monitor->model = Xcalloc(rep.modelLength + 1, 1))) {
-	    _XEatData(dpy, (rep.nhsync + rep.nvsync) * 4 +
-		      ((rep.vendorLength+3) & ~3) + ((rep.modelLength+3) & ~3));
-	    if (monitor->vendor)
-		Xfree(monitor->vendor);
-	    return False;
-	}
+    if (result && rep.modelLength) {
+	monitor->model = Xcalloc(rep.modelLength + 1, 1);
+	if (monitor->model == NULL)
+	    result = False;
     } else {
 	monitor->model = NULL;
     }
-    if (!(monitor->hsync = Xcalloc(rep.nhsync, sizeof(XF86VidModeSyncRange)))) {
-	_XEatData(dpy, (rep.nhsync + rep.nvsync) * 4 +
-		  ((rep.vendorLength+3) & ~3) + ((rep.modelLength+3) & ~3));
-
-	if (monitor->vendor)
-	    Xfree(monitor->vendor);
-	if (monitor->model)
-	    Xfree(monitor->model);
-	return False;
+    if (result) {
+	monitor->hsync = Xcalloc(rep.nhsync, sizeof(XF86VidModeSyncRange));
+	monitor->vsync = Xcalloc(rep.nvsync, sizeof(XF86VidModeSyncRange));
+	if ((monitor->hsync == NULL) || (monitor->vsync == NULL))
+	    result = False;
+    } else {
+	monitor->hsync = monitor->vsync = NULL;
     }
-    if (!(monitor->vsync = Xcalloc(rep.nvsync, sizeof(XF86VidModeSyncRange)))) {
+    if (result == False) {
 	_XEatData(dpy, (rep.nhsync + rep.nvsync) * 4 +
 		  ((rep.vendorLength+3) & ~3) + ((rep.modelLength+3) & ~3));
-	if (monitor->vendor)
-	    Xfree(monitor->vendor);
-	if (monitor->model)
-	    Xfree(monitor->model);
+	Xfree(monitor->vendor);
+	monitor->vendor = NULL;
+	Xfree(monitor->model);
+	monitor->model = NULL;
 	Xfree(monitor->hsync);
-	return False;
-    }
-    for (i = 0; i < rep.nhsync; i++) {
-	_XRead(dpy, (char *)&syncrange, 4);
-	monitor->hsync[i].lo = (float)(syncrange & 0xFFFF) / 100.0;
-	monitor->hsync[i].hi = (float)(syncrange >> 16) / 100.0;
+	monitor->hsync = NULL;
+	Xfree(monitor->vsync);
+	monitor->vsync = NULL;
     }
-    for (i = 0; i < rep.nvsync; i++) {
-	_XRead(dpy, (char *)&syncrange, 4);
-	monitor->vsync[i].lo = (float)(syncrange & 0xFFFF) / 100.0;
-	monitor->vsync[i].hi = (float)(syncrange >> 16) / 100.0;
+    else {
+	for (i = 0; i < rep.nhsync; i++) {
+	    _XRead(dpy, (char *)&syncrange, 4);
+	    monitor->hsync[i].lo = (float)(syncrange & 0xFFFF) / 100.0;
+	    monitor->hsync[i].hi = (float)(syncrange >> 16) / 100.0;
+	}
+	for (i = 0; i < rep.nvsync; i++) {
+	    _XRead(dpy, (char *)&syncrange, 4);
+	    monitor->vsync[i].lo = (float)(syncrange & 0xFFFF) / 100.0;
+	    monitor->vsync[i].hi = (float)(syncrange >> 16) / 100.0;
+	}
+	if (rep.vendorLength)
+	    _XReadPad(dpy, monitor->vendor, rep.vendorLength);
+	if (rep.modelLength)
+	    _XReadPad(dpy, monitor->model, rep.modelLength);
     }
-    if (rep.vendorLength)
-	_XReadPad(dpy, monitor->vendor, rep.vendorLength);
-    if (rep.modelLength)
-	_XReadPad(dpy, monitor->model, rep.modelLength);
-
     UnlockDisplay(dpy);
     SyncHandle();
-    return True;
+    return result;
 }
 
 Bool
-- 
1.8.2.3